I'm developing a Desktop Search Engine in VB.NET
I'm using a ComboBox to specify the search query (string).
I want the ComboBox to remember and display recent queries.
I also want the ComboBox to try and Autocomplete the queries as the user is typing.
What is the best way to implement this?
This can no doubt be done more elegantly, but here's the basic principles (apologies for any syntax issues, I'm not much of a VB guy):
In the KeyUp event:
Make sure the key in't a navigation key:
if e.KeyCode <> Keys.Back [...]
Search the items list for the text typed:
idx = myCombo.FindString(myCombo.Text)
Take the combo's found item:
s = myCombo.GetItemText(idx)
insert it into the .Text property:
myCombo.Text = s
Note that this would overtype everything the user entered (destroying case). You could improve this by appending the 'missing' part instead:
stringToAppend = s.SubString(myCombo.Text.Length)
myCombo.Text = myCombo.Text + stringToAppend
Finally, select the new text so they can keep typing:
myCombo.SelectionStart = myCombo.Text.Length - stringToAppend.Length
myCombo.SelectionLength = stringToAppend.Length
You might also want to look at this from vbAccelerator.com, offered as a basic starting point for auto-completion in VB.NET. The vbAccelerator code is usually high quality.
Related
I inherited a fairly large project at work that is undocumented and written in VB (originally started pre .NET, ended around .NET 2). I'm in the process of updating / refreshing a lot of the code, but have run into an annoying issue that I haven't found the solution for yet. This system utilizes a UI, a Web Service, and a SQL DB.
Problem: I have a Databound Combobox (originally set to DropDownList - I'm changing it to DropDown, which is what started this mess - going back isn't an option) that is tied to a DataSet that comes from a Web Service. When a user types in the item they want manually, the data from the text field doesn't seem to associate itself with the DisplayMember, which forces the WS/SQL query to fail (it is sent a blank value when it's expecting a ValueMember). If the user types in a partial selection and then chooses the value they want from the DisplayMember list using the arrow keys or tab, the query goes off without a problem.
My Question: How do I get the text field to translate to the DisplayMember which will then properly tie itself to the ValueMember which will then allow the query to execute correctly? Sorry for making this sound complicated or convoluted; I'm sure the answer is easy and I'm just glazing over it.
The relevant bit of code is:
With cmbDID
If dtsLU.Tables.Contains(reqTable) = True Then
.DataSource = dtsLU.Tables(reqTable)
.DisplayMember = "zip"
.ValueMember = "gridID"
End If
End With
cmbDID.DataBindings.Clear()
cmbDID.DataBindings.Add("SelectedValue", dtsData, strDT & ".gridID")
I've tried changing "SelectedValue" to "Text", which almost works - but it directly translates to gridID and skips zip which ends up with an incorrect Web Service response since the zip and gridID field values are not synced (zip (DisplayMember) may be 5123 while gridID (ValueMember) may be 6047). I've tried changing "SelectedValue" to "SelectedIndex", and that got me no where.
Any help is greatly appreciated.
EDIT
To add some clarification to the process, the below pseudo code / description is roughly what happens. I could post the whole module, but I feel that would just muddy the whole question even more.
Private Sub A
FormAlpha is created with 1 ComboBox in the form of a DropDown
This DropDown is populated with a DataSet
DataBinding with a blank DataSet is added to the control to keep track of the users input
End Sub
lblSubmit_Click event is triggered on FormAlpha by the user after they have populated the DropDown with their data. lblSubmit_Click calls Private Sub Submit
Private Sub Submit
BindingContext(DropDown DataSet, tableName).EndCurrentEdit() is called
DataSet.HasChanges() is processed
If changes are present, changes are processed
HERE lies the problem
If the user has manually typed in the DropDown field, but not hit an arrow key or tab, then the DataSet registers a change, but returns a null value in all fields - it knows something was entered, but that data apparently didn't pass through the DataSet for the ComboBox (ListItems or SelectedIndex didn't change / fire I'm guessing). If the user selects the item with the arrow keys, the DataSet has the proper input (I'm assuming the Data was validated by the control at this point).
If the processed data is good, a value is entered into the database
If the processed data is bad (empty), an error is returned
End Sub
If the above can't be solved with what I've provided, but someone still knows a better way to handle this type of situation, I'm all ears. Rewriting the module isn't ideal, but fixing this problem is a necessity.
Alright, while this fix may not be ideal, it is a fix none the less.
The bare bones problem was that the text value of the DropDown wasn't causing the data to actually affect the SelectedIndex / SelectedValue of the control unless you interacted with it using the arrow keys or a mouse click. So, while the DropDown would read "1234", in reality the control saw "".
The fix I have in place for this is simply calling comboBox.text = comboBox.text whenever the user hits the submit button.
I am relatively new to Access and any SQL and VBA I have picked up is self-taught, so I would really appreciate answers that are not too heavily laden with technical terms...that said, I am having an issue with allowing comboboxes to be left blank on a form if the user chooses not to input data. Also, I am using Access 2016.
Initially the problem I ran into was that if a combobox was entirely skipped and left blank, or if the user selects the combobox and then tries to move on without making a selection from the list, they got the error "You tried to assign the Null value to a variable that is not a Variant data type," and were unable to move on to any other fields on the form or to save the record being entered.
I found this article that details a possible solution, but I can't seem to get it to work. I made an unbound combobox, set the Row Source to:
SELECT EmailID, PersonalEmail FROM EmailT UNION SELECT "<N/A>","<N/A>" FROM EmailT
ORDER BY PersonalEmail;
where PersonalEmail is a field of type short text and the EmailID is an autonumber. I also followed the article's steps for formatting the combobox (column width, etc.) and set it to Limit to List = Yes.
Here is my exact code:
Private Sub Combo62_AfterUpdate()
If Combo62 = "<N/A>" Then
EmailID = Null
Else
EmailID = Combo62
End If
End Sub
Private Sub Form_Current()
If IsNull(EmailID) Then
Combo62 = "<N/A>"
Else
Combo62 = EmailID
End If
End Sub
< N/A> now shows up on my list, but if it is selected I get the error: "The value you entered isn't valid for this field. For example, you may have entered text in a numeric field or a number that is larger than the FieldSize setting permits."
Access's debugger highlights the line:
EmailID = Null
but I am not sure what steps I should take now to try and fix this.
I am completely open to other methods of allowing the combobox to be left blank if someone knows of a better way to do this also. For all I know, I am missing something really obvious! Thanks in advance for any insight!
EDIT: Thanks for your help guys, I never did figure out what exactly the problem was, but I got some advice from another forum to rethink my database design so this ended up being a null issue--it's all totally different now!
If the recordsource for your form contains a query with one-to-many relationships this error may come up. Try to use only the base table as the recordsource for the form. Use subforms if you need to display related data. The rest of the code may then be unnecessary.
I am working on a MS Word form for a client where they want the ability to count the number of words, check spelling, have a character limit, and have the rest of the form locked down so that the end user cannot change anything they are not supposed to. I have attempted to convince them that word count and character limit are redundant if we have proper instructions, however, this is what they want. They also want the form to be able to "work" even if the user does not enable macros, meaning, they want it locked and a character limit first and foremost.
I know that if we just rich text content controls and put the form into a group spell check and word count word while also "locking" the remainder of the form, except user content controls do not allow for character limits and using legacy/activex controls in a grouped form locks those controls as well.
So, for now, I have settled on using the ActiveX Textbox (this is negotiable if I have a reason to use the legacy textbox) and have achieved the minimum "workability" (if that's even a word). The only way I have figured out to check the spelling is below:
Sub chkSpelling()
Activedocument.Tables(1).Rows(26).Cells(1).Range.Text = txtRole.Text
Activedocument.Tables(1).Rows(26).Cells(1).Range.checkSpelling
txtRole.Text = Activedocument.Tables(1).Rows(26).Cells(1).Range.Text
'... so on and so forth throughout each text box
End Sub
The issue is that this is not good enough for my standards. Printing the text of each textbox (up to 1700 characters) at the bottom of the screen each time I need to check the Spelling is unacceptable. Does anyone else have any ideas?
Thank you for your assistance.
Answer with help from #bibadia
Dim doc As Document
Set doc = Documents.Add(, , wdNewBlankDocument, False)
doc.Paragraphs(1).Range.Text = txtRole.Text
doc.Paragraphs(1).Range.CheckSpelling
txtRole.Text = Replace(doc.Paragraphs(1).Range.Text, Chr(13), "")
Use CreateObject to create a new word instance
Ensure .Visible = False (I think that is the default)
Create a new document in that instance.
Copy the text to be checked into that
Spell check.
Remove the document and the Word instance.
If I understand your question correctly then,
I need to check the Spelling is unacceptable. Does anyone else have any ideas?
If text boxes are named with numbers, you might be able to use loop, and save your coding lines with time.
want the form to be able to "work" even if the user does not enable macros
If user did not enable macros, he would not be able to see form (is it User Form, you want to say) and no background macro code would run. (Tested on Ms-Excel 2007), ultimately failing all.
regarding text box control on user form
yes that can be set to character limit from properties menu, and spell check can be done using your method.
Set range2 = Documents("MyDocument.doc").Sections(2).Range
range2.CheckSpelling IgnoreUpperCase:=False, _
CustomDictionary:="MyWork.Dic", _
CustomDictionary2:="MyTechnical.Dic"
-->VB.Net VS2010
If this is a stupid question, then let me know. I can't just figure it out.
First of all, this is my question. How do I detect the changed value on those text boxes?
I have an idea that I create a another string values that have the original values and compare them right before saving or form closing event. This sample just have 3 text boxes, but I have 50 + text boxes on my one form. I can do it that way, but that is not really smart idea.
Can I use abcDB.SubmitChanges() to detect any data changes on text boxes?
Dim sqlQuery = (From obj in abcDB.HelloWorld
Select obj.Fname, obj.Lname, obj.PhoneNumber).FirstOrDefault()
me.textboxFname.text = sqlQuery.Fname
me.textboxLname.text = sqlQuery.Lname
me.textboxPhoneNumber.text = sqlQuery.PhoneNumber
What you really want to do is called 'data binding'. Lots of tutorials about that aroud the web and any book about VB.NET will have at least 1 chapter dedicated to it.
Code in Form onLoad:
country_combo.RowSourceType = "Value List"
Code in a reset function:
Dim lListIndex As Long
With Me.country_combo
For lListIndex = .ListCount - 1 To 0 Step -1
.RemoveItem (lListIndex)
Next lListIndex<br/>
End With
Code to populate country combo:
*For n = 1 To numCountries*
*countryCombo.AddItem (countryRS.Fields("countryName"))*
*countryRS.MoveNext*
*Next n*
I'm having a problem that occurs AFTER the code to populate the country combobox runs. The values are there as I can run Debug.Print(countryCombo.Value) and it prints out the name of the selected country, but I can't see the values in the combobox at all. They're invisible, and as far as I know there is no visiblity property for specific items, unless I'm completely mistaken.
comboBoxError.png http://img110.imageshack.us/my.php?image=comboboxerror.png
I think you should probably use Access's GUI tools to do what you're looking for. In design mode, click on the field you are trying to populate, then click the "lookup" tab. You can then specify a table to populate the field with and your forms should automaticly update as well.
I've also seen what you describe here - as far as I can tell, it's a bug within Access (I was using 2007) that only occurs when you programatically mess with the contents of a combo box. It does not happen every time. The issue corrects itself if you highlight the text that is in the combo box.
I am experiencing a similar issue with Access 2003. Based on the selection of one combo box, the row source of a listbox is set to an SQL string Basically a SELECT DISTINCT [MyField_Selected] FROM MyTable. For some fields the values are visible in the list box and others it is not. The values are there however as I can access them via code. To make it more interesting it works fine in Access 2007.
Just found the resolution on another forum. Check the format property of the field(s) in question on the table. In my case, when Access 2007 created the table, it put an # format in there. I removed that and all works great!